Rotary engines and motors have not been widely accepted. Rotary engines as known today are mechanically complex. They have posed significant problems with respect to temperature control. Designers of such engines have also encountered difficulty in sealing between the rotary member and the associated stationary housing. The present invention has been directed toward solutions to these problems.
One form of a rotary engine utilizes a lobed rotor rotatably mounted within an enclosing housing to form a variable fluid volume working chamber in conjunction with intake and exhaust ports. A gate valve or partition member slidably engages the periphery of the rotor to prevent fluid from moving directly from the intake port to the exhaust port. Examples of prior U.S. patents that disclose such devices are U.S. Pat. No. 884,332, issued Apr. 7, 1908; U.S. Pat. No. 2,515,288, issued Jul. 18, 1950; U.S. Pat. No. 3,924,579, issued Dec. 9, 1975; U.S. Pat. No. 4,386,894, issued Jun. 7, 1983; and U.S. Pat. No. 4,599,059, issued Jul. 8, 1986.
FIGS. 1-4 illustrate, in diagrammatic form, the operational steps of a conventional rotary engine. Such an engine typically includes a cylindrical rotor 2 that rotates in a complementary-shaped rotor chamber within a stationary housing 1. The rotor chamber has a larger diameter than that of rotor 2, resulting in formation of an annular working chamber 6 about the periphery of rotor 2. Intake and exhaust ports 3 and 4, respectively, communicate with working chamber 6.
A movable partition member 5 protrudes through housing 1 into annular working chamber 6 to separate intake port 3 from exhaust port 4. Rotor 2 includes a land or lobe 7 which further divides working chamber 6 into expansion and exhaust chambers. The expansion chamber is formed behind lobe 7, in the portion of annular working chamber 6 which trails lobe 7. The exhaust chamber is formed ahead of lobe 7, in the portion of annular working chamber 6 which leads lobe 7.
During an initial portion of rotor rotation, shown in FIG. 1, combustible gas is drawn or forced into working chamber 6 through intake port 3. The combustion gases are ignited, driving rotor 2 in a clockwise direction. Spent gases from a previous combustion cycle are exhausted ahead of lobe 7 through exhaust port 4. FIG. 2 shows a subsequent portion of rotor rotation, in which lobe 7 is approaching exhaust port 4 and working member 5. In FIGS. 3 and 4, lobe 7 has pushed working member 5 upwardly so that lobe 7 can pass thereunder. The cycle is repeated to produce continuous rotational motion.
Passage of pressurized gas directly from intake port 3 to exhaust port 4 is prevented by partition member 5 which is radially movable. It yieldably rides along the periphery of the rotor 2.
Sealing the sliding partition member, both against its seat and against the rotor, presents practical problems. Supporting the partition member against the forces of combustion presents another practical problem. In the prior art, the sealing partition member is held against the rotor periphery by yieldable biasing forces supplied by springs. However, this often results in unacceptable frictional forces between the rotor and the partition member. Furthermore, at high rotor speeds the engaging pressure of the partition member is subject to substantial variation. Such pressure in many cases is insufficient to completely close the partition member against the rotor. One object of this disclosure is to provide positive displacement controls to the partition member rather than the yieldable displacement control of previous devices. The invention described herein also provides improved opportunities for sealing the interface between the partition member, the working chamber, and the rotor, and for supporting the partition member against the explosive forces of internal combustion within the working chamber.